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From | Damian Finlayson <damian.finlayson@gmail.com> |
To | statalist@hsphsun2.harvard.edu |
Subject | Re: st: Listing the first 5 observations |
Date | Wed, 29 Aug 2012 22:19:48 +0100 |
Thanks all for your help. On 29 August 2012 15:31, Nick Cox <njcoxstata@gmail.com> wrote: > -if- and -in- are completely unrelated. Usually this is a feature, but > here it means that you have to do some work to get what you want. > > One way is > > gen OK = age == 49 > sort OK > l var1 in -5/L > > Another way is > > browse var1 if age == 49 > > where in practice you will get a screenful. > > I've not been serious about your stipulation of randomness; I guess > you mean no more than arbitrary. > > Note: one criterion; two or more criteria. > > Nick > > On Wed, Aug 29, 2012 at 3:23 PM, Damian Finlayson > <damian.finlayson@gmail.com> wrote: > >> This seems like a relatively simple query but no matter which way I >> try I cannot get it to work. >> >> I am trying to randomly select a number of observations according a >> set criteria. >> >> Say I have 3 variables: var1, var2 and random. Var1 consists purely >> of unique values (such as names). Var 2 has groups/categories (e.g. >> age). Random consists of unique random numbers. >> >> I would like to get stata to sort each category (age) by a random >> number and then list the first 5 names for a given age say 49. >> >> The command I am trying to use is: >> >> list var1 if age == 49 >> >> but I cannot seem to amend this command so that only the first 5 >> observations (as per the random number) are listed. If I use in 1/5 >> it does not work as the first observation for age 49 could be the 53 >> observation the second at 114 and so on. If I ask for all >> observations I could end up with thousands of names being listed. > * > * For searches and help try: > * http://www.stata.com/help.cgi?search > * http://www.stata.com/support/statalist/faq > * http://www.ats.ucla.edu/stat/stata/ * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/statalist/faq * http://www.ats.ucla.edu/stat/stata/